Two hydrogen atom collide head on and end up with zero kinetic energy .Each atom then emit a photon of wavelength `121.6 nm` .Which transition leads to the wavelength ?

Explanation

To determine which transition leads to the emission of a photon with a wavelength of 121.6 nm from hydrogen atoms, we can follow these steps:

### Step 1: Understand the Problem
Two hydrogen atoms collide and end up with zero kinetic energy, which means all the kinetic energy is converted into potential energy, exciting the electrons in the hydrogen atoms. After the collision, each atom emits a photon of wavelength 121.6 nm.

### Step 2: Use the Rydberg Formula
The Rydberg formula for the wavelength of emitted light during an electron transition in a hydrogen atom is given by:
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